1. Field of the Invention
The present disclosure relates to liquid droplet forming apparatuses.
2. Description of the Related Art
Conventionally, a liquid droplet forming apparatus that ejects liquid held in a liquid chamber as a droplet is known in the art. In the conventional liquid droplet forming apparatus, for example, dispersing liquid using a pigment as colorant is used as the liquid to be ejected.
However, in the dispersing liquid using a pigment as colorant, although the pigment does not precipitate by itself, the pigment may precipitate due to congelation caused by Van der Waals' forces, etc., when the dispersing liquid using a pigment as colorant is left in the liquid droplet forming apparatus for a long time. When coagula of the pigment precipitate, the liquid cannot be stably ejected due to a clogging nozzle. Therefore, the liquid needs to be dispersed again so as to prevent the coagulation of the pigment (for example, see Patent document 1).
Recently, a technology in which a plurality of cells are ejected using inkjet is developed as stem cell technology advances. A cell is a precipitating particle that precipitates upon being left for long time. Although conventional particles (such as the pigment) ejected by the conventional liquid droplet forming apparatus precipitate after being coagulated, the precipitating particle such as a cell may solely precipitates without being coagulated since the precipitating particle is heavier than a conventional particle having a diameter 100 times greater than a diameter of the conventional particle.
Therefore, when using a method for the conventional liquid droplet forming apparatus, it is difficult to sufficiently stir liquid including the precipitating particles, and variance in a number of the precipitating particles included in an ejected droplet may be caused due to the precipitation of the precipitating particles.